Sprag type clutches are known in the prior art for transmitting torque from an inner raceway to an outer raceway. The clutches have precision components known as sprags, which are rotatably mounted between annular rings that form a cage to hold the sprags in position. In addition, a majority of sprag clutches include spring biasing elements to align the sprags in a desired position when torque is not being transferred by the clutch. Typically, the spring biasing elements are mounted inside the cage, between the annular plates.
However, such a design configuration is not easy to assemble because the springs have to be inserted on the sprags before the annular plates can be connected together. Moreover, the cage is usually riveted together and not susceptible to being opened for repair or servicing if a spring should malfunction. In addition, a sprag clutch assembly can have different actuating or lift off speeds depending on the strength of the spring biasing elements being used. In general, the prior art clutches do not provide a suitable way to easily exchange different strength springs to allow different lift off speeds for the same clutch. In addition, prior sprag clutch designs utilize one spring element to resiliently bias a number of adjacent sprags. Thus, failure of one spring element can impact multiple different sprags.
One proposed sprag clutch design has spring elements located on an exterior of the sprag Clutch cage, however, each sprag is connected to its neighboring sprags by a common spring element.